The overall objective of the proposed research is to further our understanding of the structure and function of eucaryotic elongation factor 1 (EF-l) in protein synthesis, as well as to gain new information on the biosynthesis of the factor in relationship to ribosome synthesis. The biosynthesis and control of elongation factor 2 levels in different eucaryotic cells is also an important aspect of the project. In the following year our research aims include an examination of the role of the different subunits of EF-1 in a reticulocyte cell free system. We hope to answer the question of what function, if any, does the beta chain of EF-1 have. Purification of the beta chain of EF-l from rabbit reticulocyte and structural comparison to eEF-Tu. A continuation of our effort in exploring the structural and functional similarities between eEF-Tu and bacterial EF-Tu. An examination of the biosynthesis of EF-1 and EF-2 in developing sea urchin embryos.